This movie will be a reunion for Spader and RDJ. They already were in the "Less Than Zero" movie together which also had Spader's character trying to make RDJ's life miserable.
Lest we forget, LTZ was in itself a reunion, several years after Spader and Downey fought idiotic bad guys in the all-time classic TUFF TURF. Spader was top-billed then but shared the majority of his screen-time with Kim Richards.
Will Shatner play Kang in AVENGERS III???? Either way, whoever thought of Spader as Ultron is a demented genius.